Interfacial charge accumulation effect on magnetic domain wall nucleation and propagation in a Pt/Co/Pt/Al2O3 structure

We report direct observation of charge accumulation effect on magnetization reversal in a Pt/Co(0.5 nm)/Pt(0.5 nm)/Al2O3 structure with perpendicular anisotropy. By imaging magnetic domain with polar Kerr microscopy, we evidence that positive charges accumulating at the Pt/Al2O3 interface result in favoring magnetic domain wall propagation, while negative charges hinder domain wall nucleation and propagation. Our results suggest that magnetic properties in Co layer can be strongly influenced by 5d electron accumulation/depletion in an ultrathin Pt layer.
Comment: 4 pages, 4 figures, added references